We bought a Hyundai Kona EV in May - and ditched our two gas guzzling ICE vehicles - and for 3 months I purposely experimented with using only the level 1 EVSE which came with the Kona. During part of that time both my wife and I worked exclusively from home and now I'm out in the world and the wife is still working from home. Consequently, our driving was minimized when we got the Kona. Now, our driving distance is substantially higher, and will climb even higher when the wife also begins a daily commute - so much so that we will probably purchase another EV. Added to the present commuting: trips to do our shopping, shopping and other care needs for my wife's elderly parents, a few quick longish day trips, and one big quick road trip of 800 kms (500 mi.) in a single day, and the kms did add up. Those three months of charging exclusively at level 1 did teach me a few things:
1. Level 1 charging is DAMN slow. The Kona would take almost 60 hours - SIXTY! - to charge from 0 - 100%. At roughly 7 kms/hr. - or less, unless I charged every time I was at home, it was easy to get behind that energy usage curve (see #2 below). A 75 km day (about 46 mi.) would mean at least 10-11 hours on the charger. We have Peak/Off-Peak rates for our electricity and the rates more than double during peak times. Our off peak hours are 7 p.m. - 7 a.m., so there is ample incentive to restrict charging to those times. Because it takes so long to charge at level 1, I found myself trying to keep as much charge in the Kona's battery as possible so as not to get too far behind, which would mean a trip to a public EVSE. Also, after that big 800 km trip, as I limped home with a mere 2% charge left, I realized there was no way I could wait 48 hours for our level 1 EVSE to bring the state of charge up to 80%, or even provide enough juice for the next day's driving in the time available during off peak rates.
2. I found that at least once every week or two, maybe every 10 days on average, I needed to use area public level 2 AC EVSEs or occasionally a DC Fast Charger. We are fortunate to live near by a host of commercial public level 2 EVSEs - and at least a couple of free ones as well. We also have two reliable DCFCs - very much not free - within about 5 kms of our house. Free level 2 EVSEs are great, but you only get at best maybe 40 kms/hr of charging and most public level 2 EVSEs that I'm familiar with limit you to a 2 hour charge. I also found that the reliability of public chargers - level 2 and 3, free or commercial - was often spotty and unpredictable. One particular free DCFC rated at 24 kW actually provided less energy than a free public 6.6 kW level 2 EVSE during sessions of similar length. Another free level 2 EVSE had a charge curve which would continuously fluctuate from about 1.5 - 6 kW of power, rendering an average level that was maybe 4ish kW per hour. I could often schedule an hour of dog walking near a reliable free level 2 EVSE or commercial DCFC, but I realized that this was an occurrence which would not lessen over time, and the thought of needing to replicate this routine during the depths of an Ottawa winter did not exactly fill my heart with joyful anticipation. I dreaded the very thought of this part of the charging ritual come the bleak midwinter.
3. Aside from HVAC systems, ovens/cooktops, washers and dryers, and water heaters, almost no electric circuit in home service panels is designed to handle a maximum current draw for multiple hours on end. That is exactly what a level 1 EVSE is capable of doing. The one outlet available in my garage for my 12A level 1 EVSE is on a 15A circuit. A 12A load is 80% of the rated capacity of that 15A circuit, the most you can safely draw. Sounds OK, but those outlets were not necessarily designed to pull maximum loads for 12+ hours at a time. A manufacturer provided level 1 EVSE is undoubtedly OK with hours of continuous 12A current draw, since it was specifically designed to do just that. The service panel and the wiring were probably also OK with such loads, as a properly functioning circuit breaker would prevent any overload heating on the internal wiring. The weakest link in the whole system was probably the outlet in my garage into which I plugged my EVSE. Were the contacts and wiring as tight as they should be? I began to feel it was not a great idea to have such maximum loads on any circuit, or more specifically any individual outlet that was not designed to handle such a continuous high amperage draw and might not be physically up to the task.
4. The EVSE which comes with the Kona has a woefully short cable, necessitating the use of an extension cord, something Hyundai specifically recommends against. I understand why they do so, but one does need to pay attention to cable size, current rating, and cable length when using an extension cord for high current appliances. I bought the most robust 25 ft 12A three wire cord I could find and made sure it was uncoiled during each charge. But that meant I needed to take steps at keeping the junction between the EVSE and the extension cord dry during inclement weather possible over those long charge times. Yet another bothersome wrinkle to the charging routine.
After careful consideration, I determined that for our present driving needs, level 1 charging is not reliably practical, nor convenient, nor did I feel it was entirely safe on a continuous basis. We installed a NEMA 6-50 240V plug in our garage, I purchased a quality UL and ENERGY STAR rated level 2 EVSE, and my charging routine is now an afterthought. With only level 1 charging, it was a constant concern which took a great deal of forethought and planning. I found that to be an unwelcome and unnecessary bother. After making the switch to level 2 charging, I have yet to wax nostalgic about level 1 charging. I miss it not one damn bit. And I feel much safer with my present charging hardware and routine.
If you drive about 50 kms (30 miles) per day or less, it is possible to charge using only level 1, but as I noted above, what is possible might not be what is safest for your individual circuits, electric service panel, or outlets. The constant maximum load upon circuits not designed for such use and the uncertainty of the robustness of your outlets are reason enough to not use level 1 charging continuously. Obviously, the circuits and maybe even the voltage in your home are different from mine, but your concern for safety and a healthy respect for high voltage AC circuits should not be all that different. If you do plan on using primarily level 1 charging at home, it might be prudent to have an electrician inspect the outlet and service panel to make sure all of the connections and contacts are tight and that the circuit breaker is functioning as it should so as to minimize the possibility of any arcing or risk of overload or fire.
Other than avoiding the costs of purchasing a level 2 EVSE and the installation of a 240V circuit, there are no appreciable advantages to using level 1 charging. However, as I enumerated above, there are several reasons - the most compelling being a concern for safety and mitigating the risk of an electrical fire - not to use level 1 charging as your primary means of providing electrons to your EV's "tank." I now only use my level 1 charger when level 2 or 3 charging is unavailable, which over nearly 3 months was during a single instance while away from home. I have yet to meet the EV driver who has ditched level 2 charging in exchange for level 1. I know I certainly won't.
